When using Tor, website URLs change formats. Instead of websites ending in .com, .org, .net, etc., domains usually end with an “onion” suffix, identifying a “hidden service”.
Traditional search engines often use “web crawlers” to access websites on the Surface Web. This process of crawling searches the web and gathers websites that the search engines can then catalog and index. Content on the Deep (and Dark) Web, however, may not be caught by web crawlers (and subsequently indexed by traditional search engines) for a number of reasons, including that it may be unstructured, unlinked, or temporary content. As such, there are different mechanisms for navigating the Deep Web than there are for the Surface Web.
Users often navigate Dark Web sites through directories such as the “Hidden Wiki,” which organizes sites by category, similar to Wikipedia. In addition to the wikis, individuals can also search the Dark Web with search engines. These search engines may be broad, searching across the Deep Web, or they may be more specific. For instance, Ahmia, an example of a broader search engine, is one “that indexes, searches and catalogs content published on Tor Hidden Services”. In contrast, Grams is a more specific search engine “patterned after Google” where users can find illicit drugs, guns, counterfeit money, and other contraband.
When using Tor, website URLs change formats. Instead of websites ending in .com, .org, .net, etc., domains usually end with an “onion” suffix, identifying a “hidden service”. Notably, when searching the web using Tor, an onion icon displays in the Tor browser.
Tor is notoriously slow, and this has been cited as one drawback to using the service. This is because all Tor traffic is routed through at least three relays, and there can be delays anywhere along its path. In addition, speed is reduced when more users are simultaneously on the Tor network. On the other hand, increasing the number of users who agree to use their computers as relays can increase the speed on Tor.
Tor and similar networks are not the only means to reach hidden content on the web. Other developers have created tools—such as Tor2web—that may allow individuals access to Tor-hosted content without downloading and installing the Tor software. Using bridges such as Tor2web, however, does not provide users with the same anonymity that Tor offers. As such, if users of Tor2web or other bridges access sites containing illegal content—for instance, those that host child pornography—they could more easily be detected by law enforcement than individuals who use anonymizing software such as Tor.